This study aims to apply a hydrogeological approaches and analysis of the 2021 flood event of Tasi-Tolu Lagoon to achieve four specific goals. Firstly, the study seeks to determine the natural characteristics of the l...This study aims to apply a hydrogeological approaches and analysis of the 2021 flood event of Tasi-Tolu Lagoon to achieve four specific goals. Firstly, the study seeks to determine the natural characteristics of the lagoon, which include factors such as size, depth, water quality, and ecosystem composition. Secondly, the influence of precipitation on the water volume in the lagoon will be examined. This analysis involves assessing historical rainfall patterns in the region, as well as the amount and frequency of precipitation during the 2021 flood event. Thirdly, the hydrogeologic and geologic conditions of the lagoon will be evaluated. This involves examining factors such as the type and structure of the soil and bedrock, the presence of aquifers or other underground water sources, and the movement of water through the surrounding landscape. Finally, the study seeks to assess the risk of future flooding in Tasi-Tolu Lagoon, based on the insights gained from the previous analyses. Overall, this study’s goal is to provide a comprehensive understanding of the hydrogeological factors that contribute to flooding in Tasi-Tolu Lagoon. This knowledge could be used to inform flood mitigation strategies or to improve our ability to predict and respond to future flooding events in the region.展开更多
This paper investigates the accuracy of weather research and forecasting by improving coding for solar radiation forecasting for location in Dili Timor Leste. Weather Research and Forecasting (WRF) model version 3.9.1...This paper investigates the accuracy of weather research and forecasting by improving coding for solar radiation forecasting for location in Dili Timor Leste. Weather Research and Forecasting (WRF) model version 3.9.1 is used in this study for improvement purposes. The shortwave coding of WRF is used to improve in order to decrease error simulation. The importance of improving WRF coding at a specific region will reduce the bias and root mean square root when comparing to the observed data. This study uses high resolution based on the WRF modeling to stabilize the performance of forecasting. The decrease in error performance will be expected to enhance the value of renewable energy. The results show the root mean square error of the WRF default is 233 W/m<sup>2</sup> higher compared to 205 W/m<sup>2</sup> from the WRF improvement model. In addition, the Mean Bias Error (MBE) of the WRF default is obtained value 0.06 higher than 0.03 from the WRF improvement in rainy days. Meanwhile, on sunny days, the performance Root Mean Square Error (RMSE) of WRF default is 327 W/m<sup>2</sup> higher than 223 W/m<sup>2</sup> from the WRF improvement. The MBE of WRF improvement obtained 0.13 lower compared to 0.21 of WRF default coding. Finally, this study concludes that improving the shortwave code under the WRF model can decrease the error performance of the WRF simulation for local weather forecasting</span></span><span style="font-family:Verdana;">.展开更多
Study of comparison of solar power generation between the GridLAB-D tool and System Advisor Model (SAM) in Dili, Timor Leste is presented in this paper. Weather Research and Forecasting (WRF) model is used to simulate...Study of comparison of solar power generation between the GridLAB-D tool and System Advisor Model (SAM) in Dili, Timor Leste is presented in this paper. Weather Research and Forecasting (WRF) model is used to simulate solar radiation for one calendar year from January to December 2014 using six-hourly interval 1° × 1° NCEP FNL analysis data. The one calendar year results from the WRF model will be used as input data for GridLAB-D and SAM to estimate the solar power generation. GridLAB-D is an open-source and analysis tool designed to operate the distribution power systems with a high-performance algorithm. System Advisor Model version SAM 2017.9.5 is used to estimate solar power performance with Photovoltaics (PVWatts)-<span style="font-family:;" "=""> <span style="font-family:;" "="">Commercial Distributed model. This model is designed to analyze the performance and the financing of renewable energy for electricity generation. The results show the lowest solar radiation is 512 W/m<sup>2</sup> obtained in June with an average monthly power of 20.6 kW and 30.55 kW generated from the SAM model and the GridLAB-D simulator, respectively. Meanwhile, the highest solar radiation is 1100 W/m<sup>2</sup>, 1112 W/m<sup>2</sup>, 1046 W/m<sup>2</sup>, and 1077 W/m<sup>2</sup> obtained in October, November, December, and January with an average monthly power of 55.72 kW, 62.44 kW, 56.65 kW, and 56.97 kW from the SAM model, in the other hand, 48.89 kW, 51.31 kW, 55.51 kW, and 57.18 kW generated by the GridLAB-D. Finally, the results show that the performance of the GridLAB-D and the SAM model was quite good because both model precisely presented values are almost closest to each other. This study proposes that the results of solar output power from both methods, GridLAB-D and SAM can be used to design grid-connected or stand-alone electric power projects to increase the quality of electricity generation in Dili, Timor Leste.</span></span>展开更多
A study of a combination of Weather Research and Forecasting (WRF) model and Long Short Term Memory (LSTM) network for location in Dili Timor Leste is introduced in this paper. One calendar year’s results of solar ra...A study of a combination of Weather Research and Forecasting (WRF) model and Long Short Term Memory (LSTM) network for location in Dili Timor Leste is introduced in this paper. One calendar year’s results of solar radiation from January to December 2014 are used as input data to estimate future forecasting of solar radiation using the LSTM network for three months period. The WRF model version 3.9.1 is used to simulate one year’s solar radiation in horizontal resolution low scale for nesting domain 1</span><span style="font-family:""> </span><span style="font-family:Verdana;">×</span><span style="font-family:""> </span><span style="font-family:Verdana;">1 km. It is done by applying 6-hourly interval 1</span><span style="font-family:Verdana;">º</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">×</span><span style="font-family:Verdana;"> 1</span></span><span style="font-family:Verdana;">º</span><span style="font-family:""><span style="font-family:Verdana;"> NCEP FNL analysis data used as Global Forecast System (GFS). LSTM network is applied for forecasting in numerous learning problems for solar radiation forecasting. LSTM network uses two-layer LSTM architecture of 512 hidden neurons coupled with a dense output layer with linear as the model activation to predict with time steps are configured to 50 and the number of features is 1. The maximum epoch is set to 325 with batch size 300 and the validation split is 0.09. The results demonstrate that the combination of these two methods can successfully predict solar radiation where four error metrics of mean bias error (MBE), root mean square error (RMSE), normalized MBE (nMBE), and normalized RMSE (nRMSE) perform small error distribution and percentage in three months prediction where the error percentage is obtained below the 20% for nMBE and nRMSE. Meanwhile, the error distribution of RMSE is obtained below 200 W/m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> and maximum bias error is 0.07. Finally, the values of MBE, RMSE, nMBE, and nRMSE conclude that the good performance of the combination of two methods in this study can be applied to simulate any other weather variable for local necessary.展开更多
We report the results of five herpetological surveys during 2011-2013 that included visits to all districts of Timor-Leste (Aileu, Ainaro, Baucau, Bobonaro, Dili, Covalima, Ermera, Laut6m, Liquiga, Manatuto, Manufahi...We report the results of five herpetological surveys during 2011-2013 that included visits to all districts of Timor-Leste (Aileu, Ainaro, Baucau, Bobonaro, Dili, Covalima, Ermera, Laut6m, Liquiga, Manatuto, Manufahi, Viqueque) except the Oecusse exclave. Our fieldwork culminated in the discovery of one putative new frog species (genus Kaloula), at least five putative new lizard species (genera Cyrtodactylus, Cryptoblepharus, and Sphenomorphus), and two putative new snake species (genera Stegonotus and Indotyphlops). In addition, we present new distribution records of amphibians and reptiles for 11 of the country's 12 contiguous districts, along with additional natural history data. Results from our surveys increase the number of amphibian and reptiles known to occur in Timor-Leste from 22 species before our surveys began to over 60, including over 20 as yet undescribed species.展开更多
Herpetological surveys of locations in six districts of Timor-Leste(Dili, Baucau, Ermera, Liqui a, Manatuto, Viqueque) during 2010 led to the discovery of a new, high-altitude species of Cryptoblepharus from Ermera Di...Herpetological surveys of locations in six districts of Timor-Leste(Dili, Baucau, Ermera, Liqui a, Manatuto, Viqueque) during 2010 led to the discovery of a new, high-altitude species of Cryptoblepharus from Ermera District, a new country record(Hemidactylus cf. tenkatei), and the recording of two previously unvouchered species(Python r. reticulatus and Liasis m. mackloti). In this article, we summarize these new records and present numerous new district records for Timor-Leste and four records for road-killed snakes seen in West Timor(Indonesia). With the addition of the results from our 2009 survey, the update presented herein increases the confirmed number of amphibian and reptile species for Timor-Leste to 47.展开更多
Slash-and-burn practices used by farmers in prior growing periods could affect soil quality, particularly topsoil properties. This study aimed to assess soil biophysical and chemical properties at different landscape ...Slash-and-burn practices used by farmers in prior growing periods could affect soil quality, particularly topsoil properties. This study aimed to assess soil biophysical and chemical properties at different landscape levels within the watershed site. Soil samples were collected by a core method in the topsoil layer in slash-and-burn sites. Field analysis was on bulk density and porosity by the gravimetric method, while laboratory analysis was done on organic matter by the Loss on Ignitions Method and other macronutrients for crops (total nitrogen, phosphorus availability, and potassium availability) followed standard analytical methods. To see if there was a significant difference between sites, DMRT 5% was used. The results of the study showed slash-and-burn practice affects soil physical properties such that high bulk density in upstream, midstream, and downstream ranged from 1.55 g/cm<sup>3</sup> to 1.71 g/cm<sup>3</sup>, 1.55 g/cm<sup>3</sup> to 1.80 g/cm<sup>3</sup>, and 1.38 g/cm<sup>3 </sup>to 1.79 g/cm<sup>3</sup> respectively. Poor porosity in upstream, midstream, and downstream ranged from 33.91% to 40.06%, 30.38% to 41.75%, and 30.91% to 46.65%, respectively. Organic matter content was low in the upstream, midstream, and downstream areas, ranging from 2.86% to 3.39%, 2.58% to 3.88%, and 2.91% to 3.88%, respectively. However, soil pH remains neutral, and nitrogen levels are low but near-optimal in the upstream and very low in the midstream and downstream. Phosphorus is extremely high upstream but very low in midstream and downstream. However, potassium remains at a low level close optimum level in the entire watershed.展开更多
Timor island has a tropical climate with relatively little rainfall and surface water is often not available throughout the year with groundwater relied on to fulfill daily domestic necessities. Geological reconnaissa...Timor island has a tropical climate with relatively little rainfall and surface water is often not available throughout the year with groundwater relied on to fulfill daily domestic necessities. Geological reconnaissance mapping, hydrogeological investigation, and resistivity survey were undertaken in this study to systematically understand the hydrogeologic system (e.g., aquifer system, hydrostratigraphic units, groundwater flow direction) and its potentiality for water supply to human consumption in Alaua Kraik area, Baucau Municipality, Timor-Leste. Res2DInv, Dips 5.1, Surfer 16, Global Mapper 13, and ArcGIS 10.6 software was used to create geological reconnaissance maps, resistivity interpretation profile lines, and a hydrostratigraphic model. Rainfall precipitation, rainfall intensity, maximum rate of runoff and infiltration data are also used to interpret the groundwater potential in the study area. Two rock units occur in the study area;permeable alluvial deposits which unconformable overlie impermeable interbedded red marl-chert and calcareous shale. Structurally the area comprises the Lacamutu anticline, thrust fault, left slip fault, and normal right slip fault. Resistivity lines indicate three (3) types of lithologies: alluvial deposit, an intercalated layer of red marl-chert, calcareous shale and wet calcareous shale. The alluvial deposit and red marl-chert layer intercalated with calcareous shale units are classified as a hydrostratigraphic unit of intergranular and localised aquifer systems with low productivity. The groundwater flows through the existing fractures of the shear joint and tends to flow towards the left slip fault plane zone from the North to South direction. Much of the rainwater in the study area is most likely intercepted, evaporated, and or transpiration as opposed to running off and infiltrating into the ground. The permeable and heavily fractured impermeable rock units in the study area have good porosity but low permeability and represent poor aquifers. The springs and Lacamutu River have low discharge and are generally dry in the dry season as it does not have an adequate aquifer that can accumulate and pass groundwater with significant volumes even if the rainfall in the study area is classified as moderate rainfall.展开更多
文摘This study aims to apply a hydrogeological approaches and analysis of the 2021 flood event of Tasi-Tolu Lagoon to achieve four specific goals. Firstly, the study seeks to determine the natural characteristics of the lagoon, which include factors such as size, depth, water quality, and ecosystem composition. Secondly, the influence of precipitation on the water volume in the lagoon will be examined. This analysis involves assessing historical rainfall patterns in the region, as well as the amount and frequency of precipitation during the 2021 flood event. Thirdly, the hydrogeologic and geologic conditions of the lagoon will be evaluated. This involves examining factors such as the type and structure of the soil and bedrock, the presence of aquifers or other underground water sources, and the movement of water through the surrounding landscape. Finally, the study seeks to assess the risk of future flooding in Tasi-Tolu Lagoon, based on the insights gained from the previous analyses. Overall, this study’s goal is to provide a comprehensive understanding of the hydrogeological factors that contribute to flooding in Tasi-Tolu Lagoon. This knowledge could be used to inform flood mitigation strategies or to improve our ability to predict and respond to future flooding events in the region.
文摘This paper investigates the accuracy of weather research and forecasting by improving coding for solar radiation forecasting for location in Dili Timor Leste. Weather Research and Forecasting (WRF) model version 3.9.1 is used in this study for improvement purposes. The shortwave coding of WRF is used to improve in order to decrease error simulation. The importance of improving WRF coding at a specific region will reduce the bias and root mean square root when comparing to the observed data. This study uses high resolution based on the WRF modeling to stabilize the performance of forecasting. The decrease in error performance will be expected to enhance the value of renewable energy. The results show the root mean square error of the WRF default is 233 W/m<sup>2</sup> higher compared to 205 W/m<sup>2</sup> from the WRF improvement model. In addition, the Mean Bias Error (MBE) of the WRF default is obtained value 0.06 higher than 0.03 from the WRF improvement in rainy days. Meanwhile, on sunny days, the performance Root Mean Square Error (RMSE) of WRF default is 327 W/m<sup>2</sup> higher than 223 W/m<sup>2</sup> from the WRF improvement. The MBE of WRF improvement obtained 0.13 lower compared to 0.21 of WRF default coding. Finally, this study concludes that improving the shortwave code under the WRF model can decrease the error performance of the WRF simulation for local weather forecasting</span></span><span style="font-family:Verdana;">.
文摘Study of comparison of solar power generation between the GridLAB-D tool and System Advisor Model (SAM) in Dili, Timor Leste is presented in this paper. Weather Research and Forecasting (WRF) model is used to simulate solar radiation for one calendar year from January to December 2014 using six-hourly interval 1° × 1° NCEP FNL analysis data. The one calendar year results from the WRF model will be used as input data for GridLAB-D and SAM to estimate the solar power generation. GridLAB-D is an open-source and analysis tool designed to operate the distribution power systems with a high-performance algorithm. System Advisor Model version SAM 2017.9.5 is used to estimate solar power performance with Photovoltaics (PVWatts)-<span style="font-family:;" "=""> <span style="font-family:;" "="">Commercial Distributed model. This model is designed to analyze the performance and the financing of renewable energy for electricity generation. The results show the lowest solar radiation is 512 W/m<sup>2</sup> obtained in June with an average monthly power of 20.6 kW and 30.55 kW generated from the SAM model and the GridLAB-D simulator, respectively. Meanwhile, the highest solar radiation is 1100 W/m<sup>2</sup>, 1112 W/m<sup>2</sup>, 1046 W/m<sup>2</sup>, and 1077 W/m<sup>2</sup> obtained in October, November, December, and January with an average monthly power of 55.72 kW, 62.44 kW, 56.65 kW, and 56.97 kW from the SAM model, in the other hand, 48.89 kW, 51.31 kW, 55.51 kW, and 57.18 kW generated by the GridLAB-D. Finally, the results show that the performance of the GridLAB-D and the SAM model was quite good because both model precisely presented values are almost closest to each other. This study proposes that the results of solar output power from both methods, GridLAB-D and SAM can be used to design grid-connected or stand-alone electric power projects to increase the quality of electricity generation in Dili, Timor Leste.</span></span>
文摘A study of a combination of Weather Research and Forecasting (WRF) model and Long Short Term Memory (LSTM) network for location in Dili Timor Leste is introduced in this paper. One calendar year’s results of solar radiation from January to December 2014 are used as input data to estimate future forecasting of solar radiation using the LSTM network for three months period. The WRF model version 3.9.1 is used to simulate one year’s solar radiation in horizontal resolution low scale for nesting domain 1</span><span style="font-family:""> </span><span style="font-family:Verdana;">×</span><span style="font-family:""> </span><span style="font-family:Verdana;">1 km. It is done by applying 6-hourly interval 1</span><span style="font-family:Verdana;">º</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">×</span><span style="font-family:Verdana;"> 1</span></span><span style="font-family:Verdana;">º</span><span style="font-family:""><span style="font-family:Verdana;"> NCEP FNL analysis data used as Global Forecast System (GFS). LSTM network is applied for forecasting in numerous learning problems for solar radiation forecasting. LSTM network uses two-layer LSTM architecture of 512 hidden neurons coupled with a dense output layer with linear as the model activation to predict with time steps are configured to 50 and the number of features is 1. The maximum epoch is set to 325 with batch size 300 and the validation split is 0.09. The results demonstrate that the combination of these two methods can successfully predict solar radiation where four error metrics of mean bias error (MBE), root mean square error (RMSE), normalized MBE (nMBE), and normalized RMSE (nRMSE) perform small error distribution and percentage in three months prediction where the error percentage is obtained below the 20% for nMBE and nRMSE. Meanwhile, the error distribution of RMSE is obtained below 200 W/m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> and maximum bias error is 0.07. Finally, the values of MBE, RMSE, nMBE, and nRMSE conclude that the good performance of the combination of two methods in this study can be applied to simulate any other weather variable for local necessary.
文摘We report the results of five herpetological surveys during 2011-2013 that included visits to all districts of Timor-Leste (Aileu, Ainaro, Baucau, Bobonaro, Dili, Covalima, Ermera, Laut6m, Liquiga, Manatuto, Manufahi, Viqueque) except the Oecusse exclave. Our fieldwork culminated in the discovery of one putative new frog species (genus Kaloula), at least five putative new lizard species (genera Cyrtodactylus, Cryptoblepharus, and Sphenomorphus), and two putative new snake species (genera Stegonotus and Indotyphlops). In addition, we present new distribution records of amphibians and reptiles for 11 of the country's 12 contiguous districts, along with additional natural history data. Results from our surveys increase the number of amphibian and reptiles known to occur in Timor-Leste from 22 species before our surveys began to over 60, including over 20 as yet undescribed species.
基金Financial assistance for equipment and supplies was partially provided by a Title V Grant to Victor Valley CollegePartial financing of student travel was provided by the Associated Student Body at Victor Valley College
文摘Herpetological surveys of locations in six districts of Timor-Leste(Dili, Baucau, Ermera, Liqui a, Manatuto, Viqueque) during 2010 led to the discovery of a new, high-altitude species of Cryptoblepharus from Ermera District, a new country record(Hemidactylus cf. tenkatei), and the recording of two previously unvouchered species(Python r. reticulatus and Liasis m. mackloti). In this article, we summarize these new records and present numerous new district records for Timor-Leste and four records for road-killed snakes seen in West Timor(Indonesia). With the addition of the results from our 2009 survey, the update presented herein increases the confirmed number of amphibian and reptile species for Timor-Leste to 47.
文摘Slash-and-burn practices used by farmers in prior growing periods could affect soil quality, particularly topsoil properties. This study aimed to assess soil biophysical and chemical properties at different landscape levels within the watershed site. Soil samples were collected by a core method in the topsoil layer in slash-and-burn sites. Field analysis was on bulk density and porosity by the gravimetric method, while laboratory analysis was done on organic matter by the Loss on Ignitions Method and other macronutrients for crops (total nitrogen, phosphorus availability, and potassium availability) followed standard analytical methods. To see if there was a significant difference between sites, DMRT 5% was used. The results of the study showed slash-and-burn practice affects soil physical properties such that high bulk density in upstream, midstream, and downstream ranged from 1.55 g/cm<sup>3</sup> to 1.71 g/cm<sup>3</sup>, 1.55 g/cm<sup>3</sup> to 1.80 g/cm<sup>3</sup>, and 1.38 g/cm<sup>3 </sup>to 1.79 g/cm<sup>3</sup> respectively. Poor porosity in upstream, midstream, and downstream ranged from 33.91% to 40.06%, 30.38% to 41.75%, and 30.91% to 46.65%, respectively. Organic matter content was low in the upstream, midstream, and downstream areas, ranging from 2.86% to 3.39%, 2.58% to 3.88%, and 2.91% to 3.88%, respectively. However, soil pH remains neutral, and nitrogen levels are low but near-optimal in the upstream and very low in the midstream and downstream. Phosphorus is extremely high upstream but very low in midstream and downstream. However, potassium remains at a low level close optimum level in the entire watershed.
文摘Timor island has a tropical climate with relatively little rainfall and surface water is often not available throughout the year with groundwater relied on to fulfill daily domestic necessities. Geological reconnaissance mapping, hydrogeological investigation, and resistivity survey were undertaken in this study to systematically understand the hydrogeologic system (e.g., aquifer system, hydrostratigraphic units, groundwater flow direction) and its potentiality for water supply to human consumption in Alaua Kraik area, Baucau Municipality, Timor-Leste. Res2DInv, Dips 5.1, Surfer 16, Global Mapper 13, and ArcGIS 10.6 software was used to create geological reconnaissance maps, resistivity interpretation profile lines, and a hydrostratigraphic model. Rainfall precipitation, rainfall intensity, maximum rate of runoff and infiltration data are also used to interpret the groundwater potential in the study area. Two rock units occur in the study area;permeable alluvial deposits which unconformable overlie impermeable interbedded red marl-chert and calcareous shale. Structurally the area comprises the Lacamutu anticline, thrust fault, left slip fault, and normal right slip fault. Resistivity lines indicate three (3) types of lithologies: alluvial deposit, an intercalated layer of red marl-chert, calcareous shale and wet calcareous shale. The alluvial deposit and red marl-chert layer intercalated with calcareous shale units are classified as a hydrostratigraphic unit of intergranular and localised aquifer systems with low productivity. The groundwater flows through the existing fractures of the shear joint and tends to flow towards the left slip fault plane zone from the North to South direction. Much of the rainwater in the study area is most likely intercepted, evaporated, and or transpiration as opposed to running off and infiltrating into the ground. The permeable and heavily fractured impermeable rock units in the study area have good porosity but low permeability and represent poor aquifers. The springs and Lacamutu River have low discharge and are generally dry in the dry season as it does not have an adequate aquifer that can accumulate and pass groundwater with significant volumes even if the rainfall in the study area is classified as moderate rainfall.